High efficiency video coding (HEVC) includes various encoding tools taking the encoding efficiency into consideration. One of the encoding tools is various prediction modes.
When a prediction mode is determined, an encoding apparatus typically calculates a cost of each prediction mode by adding a value obtained by multiplying a bit generation amount by a weighting factor (which depends on a quantization parameter Qp) and a distortion amount, and selects a prediction mode having the smallest cost as an optimal prediction mode.
Further, for example, Patent Document 1 proposes operation amount reduction in prediction mode selection in the case of H.264 and MPEG-4 Part 10 (advanced video coding, hereinbelow, referred to as AVC).